Minimally- invasive Conventional right colectomy versus complete mesocolic excision for right-colon adenocarcinoma: a single-institution cohort

Minimally- invasive Conventional right colectomy versus complete mesocolic excision for right-colon adenocarcinoma: a single-institution cohort | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Minimally- invasive Conventional right colectomy versus complete mesocolic excision for right-colon adenocarcinoma: a single-institution cohort Rodrigo Moisés de Almeida Leite, Lucas Pilotto Ramos, Ana Sarah Portilho, and 8 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6155030/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Introduction : The benefits of complete mesocolic excision (CME) versus conventional right colectomy (CRH) in right-side colon cancer remain to be defined, as it relates to reduced nodal recurrence and increase in disease-free survival (DFS). Optimal patient selection also seems to play a crucial role in choosing the best surgical technique for right-colon cancer. Methods : a retrospective analysis of a prospective, single center database analyzing minimally-invasive CME vs CRH in right side colon cancer. Only patients with free surgical margins and without distant metastasis were included for analysis. Outcomes analyzed included local recurrence, nodal recurrence, DFS, length of stay, node harvesting and major postoperative complications. The analysis was adjusted for multiple confounders, including Age; Sex; BMI; Pathologic T stage; Pathologic N stage; Mismatch repair protein deficiency; Adjuvant chemotherapy ; First postoperative CEA level; ASA score. Results : CME presented a similar safety profile, with increased in lymph node yield. CME was associated with a significant reduction in the risk for nodal recurrence (adjusted RR = 0.08; 95% CI: 0.05 to 0.09; p < 0.001). Also in the propensity-score matching analysis, CME was associated with a significant coefficient of reduction for nodal recurrence (Coef . = -0.14; 95% CI: - 0.23 to -0.05; p = 0.01). An improvement in disease-free survival was also observed (HR = 0.03; 95% CI: 0.003 to 0.27; p = 0.002) in patients with pT3/pT4 or pN+ disease. Meaning : Minimally-invasive CME may be associated with decrease in nodal recurrence and increase disease-free survival in patients with right colon cancer. colon cancer complete mesocolic excision colorectal cancer D3 lymphadectomy right colon-cancer central vessel ligation robotic surgery laparoscopic surgery minimally invasive colectomy Figures Figure 1 Figure 2 Introduction Colorectal cancer (CRC) is a leading cause of cancer-related morbidity and mortality worldwide. In right colon cancer, the concept of Complete Mesocolic Excision (CME) has gained traction as a potentially superior surgical approach compared to conventional right colectomy. Introduced by Hohenberger in 2009 (01), CME involves meticulous dissection along embryological planes to achieve an intact mesocolon with a higher yield of lymph nodes, which theoretically reduces the risk of local recurrence and improves disease-free survival (DFS) rates. (02) A recent systematic review (03) and meta-analysis, however, has failed to demonstrate significant improvement in three-year overall survival and disease-free survival with CME approach, in addition to no difference in local recurrence and no difference in distant recurrence, in spite of significant increase in 5-year overall survival. Several factors may play a role in this, such as an overall low incidence of local recurrence after curative resection of colon cancer and adjuvant chemotherapy. (04) Patient selection may play a crucial role in choosing CME as a technical approach. For more advanced cases or right colon cancer - stages III/IV -, a survival benefit has been more constant in observational trials (05). This may be due to a relative higher incidence - of around 8 % ) of central nodes metastasis in T3 or T4 right colon tumors. (06,07) The safety of the CME procedure itself is also a matter of debate. Due to the higher distance of the vascular tie and greater mesentery mobilization, it may be associated with greater intraoperative blood loss (08) and postoperative complications. A recent prospective study (09), however, has shown similar complications rates when it is conducted in experienced centers. In order to analyze this relevant clinical question, we conducted a retrospective analysis of a prospective database of a single center specialized in minimally invasive surgery for colon cancer, comparing the short term safety and long term survival of CME versus conventional right colectomy for the management of right-sided colon cancer. Methods Study design A retrospective analysis of database of patients undergoing elective surgery for right side colon cancer in Albert Einstein Israelite Hospital Sao Paulo, Brazil. All procedures were performed by any of the six experienced oncology surgeons. No learning-curve cases were included for analysis. The research was granted ethical approval by the Institutional Review Board of Hospital Israelita Albert Einstein, which exempted the requirement for informed consent (Protocol Number: CAAE 68495923.6.0000.0071 and in Hospital Albert Einstein IRB ( protocol 6142-24). In alignment with ethical standards, personal identifiers were anonymized. The study also complied with the Brazilian General Data Protection Law (Lei Geral de Proteção de Dados - LGPD) by taking appropriate protective measures. Anonymization techniques were employed to remove any information that could reveal the identities of the subjects. Inclusion criteria We included adult (>18 years old) patients diagnosed with right-colon adenocarcinoma. Only minimally invasive right colectomies (laparoscopic or robotic) were considered. The inclusion period was from 2019 to 2024. Exclusion criteria Presence of a second primary tumor. In addition, for survival analysis, we included only patients with the following findings in the initial pathologic staging for disease-free survival comparison. pathologic T3 or T4 tumor; Any T status with nodal involvement (N1 or higher ); Surgical margins free of disease; Absence of metastatic disease upon diagnosis. Groups of study Surgical Procedures Only minimally invasive cases - laparoscopic or robotic- were included. Robotic technique : Da Vinci robot was utilized for the cases. A single docking with 4 robotic arms, positioned in a straight line from the right iliac region to the xiphoid, plus an auxiliary 12 mm laparoscopic portar were placed. The patient is positioned in a supine position with mild left decubitus and Trendelenburg. Laparoscopic technique : Five trocars are placed for the procedure, one 11 mm in the umbilicus for the optics, one 12 mm in the left upper quadrant, and 3 5 mm in the remainder quadrants. The patient is positioned in a supine position, with mild left decubitus and Trendelemburg. At the time of the anastomosis, the patient is returned to a neutral position. In both approaches, a laparoscopic advanced bipolar scalpel and laparoscopic linear staples were used in the procedure. For the ligation of vessels, only advanced bipolar energy was used, without clips. The anastomosis were lateral, ileal-colonic, isoperistaltic, using 60-mm mid-width linear staplers, concluded with barbed-wire suture. The specimen was retrieved via Maylard auxiliary incision. We considered complete mesocolic excision (CME) as right colectomy with central ligation of ileocolic, right colonic and right branch of colon vessels; mesenteric dissection along the embyologic layers; and D3 lymphadenectomy - including Superior Mesenteric Vein (SMV) and lateral Superior mesenteric artery (SMA) lymph nodes. Traditional or conventional right colectomy included ligation of the ileocolic vessels in the SMV root after its exposure, without additional dissection of the D3 nodes. Postoperative Assessments and Endpoints Primary outcome Our primary outcome was locoregional recurrence, defined as either nodal disease or local recurrence after follow-up for cancer was initiated. Nodal disease was considered positive if imaging findings or pathologic results were indicative of adenocarcinoma recurrence. All patients underwent pos-operative surveillance according to ASCO guidelines, including clinical encounter with clinical oncologist every 3 months, CEA monitoring and anual CT-scan of the chest, abdomen and pelvis. Disease-free survival was defined as the absence of locoregional or distant recurrence after surgery. Secondary outcomes The secondary outcomes were: Operative time; In-hospital stay; Number of harvested lymph nodes; Post-operative surgical complications (including bleeding, unplanned conversion, deep surgical site infection, superficial surgical site infections, anastomotic leak, and death) within 30 days. Statistical analysis We conducted survival analysis for disease-free survival counting in months from the operation date - if no adjuvant chemotherapy was conducted - or from the end of adjuvant chemotherapy to build Kaplan-Meier survival curves and to obtain adjusted hazard ratios through Cox regression. We also conducted multivariate Poisson regression to obtain risk ratios for loco-regional recurrence across groups after adjusting for: Age; Sex; BMI; Pathologic T stage; Pathologic N stage; Mismatch repair protein deficiency; Adjuvant chemotherapy ; First postoperative CEA level; ASA score In addition, we conducted propensity score matching using STATA nearest neighbor modeling, matching the cohorts by the same variables to analyze our primary outcome more homogeneously. We also conducted univariate and multivariate analyses adjusted for the same confounders for our secondary outcomes utilizing Poisson regression. Due to the relevance of patient selection for CME, we also included a Bayesian variable inclusion regression map, visually highlighting the strongest predictors for nodal recurrence. All analyses were conducted in STATA 18 for Mac, Standard Edition (serial number: 401806341276. Licensed to: Rodrigo Moisés de Almeida Leite; Harvard Medical School). Results Demographics Overall, 154 cases were included for analysis, 26 in the CME cohort, and 128 in the conventional cohort. After applying inclusion and exclusion criteria for the survival analysis, the cohort comprised 26 CME cases and 63 cases in the conventional cohort. The median age recorded was 65 years old (IQR 60-76) in the conventional cohort and 65.5 years (IQR 55-70) in the CME cohort. Female patients comprised 55.6% of conventional cases and 53.8% of CME cases. There were no significant differences between the groups regarding T or N status and ASA Scores. Patients also had similar baseline characteristics, such as pre-operative hemoglobin and albumin levels. Demographics are summarized in table 1. Locoregional recurrence No local recurrences were observed in either group. Nodal recurrence was observed in 6 patients in the conventional cohort (incidence of 9.52%). No nodal recurrence was observed in the CME group. The mean time for nodal recurrence was 28 months (SD 10 months). The strongest predictors for nodal recurrence were pT4 and pN2 stages. Predictors for nodal recurrence are summarized in the Bayesian Regression Model Variable inclusion map (Figure 1). Complete mesocolic excision was associated with a significant decrease in nodal recurrence in the various models for analysis conducted. After adjusting for multiple confounders using Poisson Regression, CME was associated with a significant reduction in the risk for nodal recurrence (adjusted RR = 0.08; 95% CI: 0.05 to 0.09; p < 0.001). Also in the propensity-score matching analysis, CME was associated with a significant coefficient of reduction for nodal recurrence (Coef . = -0.14; 95% CI: - 0.23 to -0.05; p = 0.01). Our post PSM validation is presented in table 2. Our Bayesian regression variables inclusion map shows that pathologic T3, T4 and N positive patients were strongly associated with increased nodal recurrence. Disease-free survival Disease-free survival was significantly increased in the CME cohort, as demonstrated in the Kaplan-Meier curve ( figure 2). The multivariate survival-time Cox regression showed a significant increase in disease-free survival (HR = 0.03; 95% CI: 0.003 to 0.27; p = 0.002) for the CME treated group. Only one case of death was recorded during the period of follow-up, preventing comparison of overall survival. Postoperative Outcomes Operative Time CME was associated with a significant increase in total operative time. Median operative time was 135 minutes in the conventional cohort (IQR 109-167), compared to 161 minutes in the CME cohort (IQR 145-200). Surgical outcomes are summarized in table 2. In-hospital stay There was no significant difference between groups regarding in-hospital stay. Median in-hospital stay was 3 days in the CME cohort (IQR 2-5) and 2 days (IQR 2-3) in the conventional group. Surgical outcomes are summarized in table 2. Harvested lymph nodes CME was associated with a significant increase in harvested lymph nodes, with 8 extra nodes on average. The median number of nodes was 31 in the conventional cohort (IQR 24-35) and 39 in the CME cohort (IQR 29-45). CME was not associated with positive pathologic nodal disease (40 % vs 31 %, RR 1.28, 95 % CI 0.38 - 4.29), p 0.692). Surgical outcomes are summarized in table 2. Postoperative complications The incidence of major postoperative complications was 23.53 % in the CME group and 18.75% in the conventional group. There was no significant difference in the incidence of major surgical complications both in the univariate (RR = 1.31; 95 % CI: 0.54 to 3.19; p = 0.539) and in the multivariate regression (adjusted RR = 0.93; 95% CI: 0.35 to 2.46; p = 0.896). Only one case of major intraoperative bleeding was reported in the CME cohort, with need of intraoperative blood transfusion. Surgical outcomes are summarized in table 2. Discussion In this retrospective cohort study, minimally-invasive complete mesocolic excision (CME) was associated with reduced nodal recurrence and increase disease-free survival when compared to minimally invasive conventional D2 right colectomy. The benefits were observed even after multiple adjustment and regression methods to reduce the risk for bias and confounding. These findings may translate to a survival benefit of this approach in click practice. CME in our study was associate with a higher number of harvested lymph nodes. The CME group had a median of 39 lymph nodes compared to 31 in the conventional group, yielding an average of eight additional nodes. This increased lymph node retrieval has been demonstrated in multiple studies comparing CME to conventional techniques, of around 8 additional harvested nodes ( 09 ), and may be associated with more accurate staging, increase in adjuvant chemotherapy and reduced recurrence (11). Our study showed a significant association of CME with reduced nodal recurrence. Nodal recurrence was observed in 9.52% of patients in the conventional cohort as opposed to zero events in the CME cohort. The mean time to nodal recurrence was 28 months. The strongest predictors for local recurrence were pT4 and pN2 stages, as consistent with the literature. CME showed a consistent reduction in nodal recurrence risk across various models, including adjusted and propensity-score matching analyses. Our analysis was also associated with a significant improvement in disease-free survival (DFS) for patients undergoing CME, as demonstrated in the Kaplan-Meier and Cox-regression model. Patient selection may play a crucial role in this outcome. We only included for our survival analysis patients with pT3, pT4 or pN + disease. The recent RELARC trial (12) failed to show a significant improvement in 3 years DFS with CME, but the profile of patients was different, with inclusion of pT2N0 patients. Also, the location of tumors within the right colon (cecum vs hepatic flexure tumors) (13) is also associated with differences in central nodes metastasis and may affect findings. Our findings correlate, however, with a recent systematic review (9) showing a survival improved DFS with the same profile of patients included in our analysis. CME was associated with a longer operative time compared to conventional colectomy, with median times of 161 minutes for CME and 135 minutes for conventional surgery. This increase is expected given the complexity of the CME procedure, which involves more extensive dissection and mesentery mobilization. Despite the longer operative time, the median in-hospital stay did not differ significantly between the two groups, indicating that the longer surgery duration does not necessarily lead to extended hospitalization or increased postoperative morbidity. The incidence of major postoperative complications was not significantly different between the CME and conventional groups. Major complications occurred in 23.1% of CME patients and 17.5% of conventional colectomy patients, with no statistically significant difference in both univariate (RR = 1.31; 95% CI: 0.54 to 3.19; p = 0.539) and multivariate analyses (adjusted RR = 0.93; 95% CI: -0.35 to 2.46; p = 0.896). Notably, we did not record any event of superior mesenteric artery lesion of major vascular event. This shows the good safety profile of the CME procedure when conducted in specialized, high volume centers. Our study has several limitations. Due to the observational nature, the risk of residual bias cannot be excluded. Also, factors as the decision to conduct CME in the first place may be associated with selection bias and inter-surgeon variation. In addition, nodal recurrence had an overall low incidence (only 6 cases), with may impact in model overfitting for our multivariate analysis. We also observed a trend towards greater robotic approach in the CME cohort, which may impact results. However, we conducted multiple adjustments to reduce the influence of bias and systematic error, and all procedures were conducted by the same team of specialized surgeons in a high volume academic center for the treatment of colon cancer. Conclusion Our study demonstrates that CME is a safe and feasible surgical technique for the management of right-side colon adenocarcinoma, associated with increased lymph node yield and comparable post-operative recovery. Also, our results point to improved oncological outcomes and increased disease survival when it was performed for a select group of high risk patients - T3, T4, N positive without distant metastasis upon diagnosis. Declarations Conflicts of interest : Drs. Leite, Ramos, Portilho, Tustumi, Stolzemburg, Gerbasi, Horcel, Pandini, Ricciardi, Seid and Araujo have no conflicts of interest related to the topic to disclose. Funding : This study was self funded. References Hohenberger W, Weber K, Matzel K, Papadopoulos T, Merkel S. Standardized surgery for colonic cancer: complete mesocolic excision and central ligation--technical notes and outcome. Colorectal Dis . 2009;11(4):354-365. doi:10.1111/j.1463-1318.2008.01735.x West NP, Hohenberger W, Weber K, Perrakis A, Finan PJ, Quirke P. Complete mesocolic excision with central vascular ligation produces an oncologically superior specimen compared with standard surgery for carcinoma of the colon. J Clin Oncol . 2010;28(2):272-278. doi:10.1200/JCO.2009.24.1448 De Lange G, Davies J, Toso C, Meurette G, Ris F, Meyer J. Complete mesocolic excision for right hemicolectomy: an updated systematic review and meta-analysis. Tech Coloproctol . 2023;27(11):979-993. doi:10.1007/s10151-023-02853-8 Malakorn S, Ouchi A, Hu CY, et al. Tumor Sidedness, Recurrence, and Survival After Curative Resection of Localized Colon Cancer. Clin Colorectal Cancer . 2021;20(1):e53-e60. doi:10.1016/j.clcc.2020.08.007 Mazzarella G, Muttillo EM, Picardi B, Rossi S, Muttillo IA. Complete mesocolic excision and D3 lymphadenectomy with central vascular ligation in right-sided colon cancer: a systematic review of postoperative outcomes, tumor recurrence and overall survival. Surg Endosc . 2021;35(9):4945-4955. doi:10.1007/s00464-021-08529-4 Paquette IM, Madoff RD, Sigurdson ER, Chang GJ (2018) Impactof proximal vascular ligation on survival of patients with coloncancer. Ann Surg Oncol 25:38–4547. Sammour T, Malakorn S, Thampy R, Kaur H, Bednarski BK,Messick CA, Taggart M, Chang GJ, You YN (2019) Selectivecentral vascular ligation (D3 lymphadenectomy) in patients under-going minimally invasive complete mesocolic excision for coloncancer: optimizing the risk–benefit equation. Color Dis 22:53–61 Wang C, Gao Z, Shen K, et al. Safety, quality and effect of complete mesocolic excision vs non-complete mesocolic excision in patients with colon cancer: a systemic review and meta-analysis. Colorectal Dis . 2017;19(11):962-972. doi:10.1111/codi.13900 Ferri V, Vicente E, Quijano Y, Duran H, Diaz E, Fabra I, Malave L, Agresott R, Isernia R, Cardinal-Fernandez P, Ruiz P, Nola V, de Nobili G, Ielpo B, Caruso R. Right-side colectomy with complete mesocolic excision vs conventional right-side colectomy in the treatment of colon cancer: a systematic review and meta-analysis. Int J Colorectal Dis. 2021 Sep;36(9):1885-1904. doi: 10.1007/s00384-021-03951-5. Epub 2021 May 13. PMID: 33983451. Willard CD, Kjaestad E, Stimec BV, Edwin B, Ignjatovic D; RCC Study Group. Preoperative anatomical road mapping reduces variability of operating time, estimated blood loss, and lymph node yield in right colectomy with extended D3 mesenterectomy for cancer. Int J Colorectal Dis . 2019;34(1):151-160. doi:10.1007/s00384-018-3177-5 Bamboat ZM, Deperalta D, Dursun A, Berger DL, Bordeianou L. Factors affecting lymph node yield from patients undergoing colectomy for cancer. Int J Colorectal Dis . 2011;26(9):1163-1168. doi:10.1007/s00384-011-1240-6 Lu J, Xing J, Zang L, Zhang C, Xu L, Zhang G, He Z, Sun Y, Feng Y, Du X, Hu S, Chi P, Huang Y, Wang Z, Zhong M, Wu A, Zhu A, Li F, Xu J, Kang L, Suo J, Deng H, Ye Y, Ding K, Xu T, Zhang Y, Zhang Z, Zheng M, Su X, Xiao Y; RELARC study group. Extent of Lymphadenectomy for Surgical Management of Right-Sided Colon Cancer: The Randomized Phase III RELARC Trial. J Clin Oncol. 2024 Nov 20;42(33):3957-3966. doi: 10.1200/JCO.24.00393. Epub 2024 Aug 27. PMID: 39190853. Bertelsen CA, Kirkegaard-Klitbo A, Nielsen M, Leotta SM, Daisuke F, Gögenur I. Pattern of Colon Cancer Lymph Node Metastases in Patients Undergoing Central Mesocolic Lymph Node Excision: A Systematic Review. Dis Colon Rectum. 2016 Dec;59(12):1209-1221. doi: 10.1097/DCR.0000000000000658. PMID: 27824707. Tables Tables 1 and 2 are available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Table1CMETechniques.pdf PostPSMTable2.pdf SemTtulo.pdf Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6155030","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":449250581,"identity":"abfdc53c-8436-4b4e-bab5-727ecedce078","order_by":0,"name":"Rodrigo Moisés de Almeida 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12:29:25","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":43086,"visible":true,"origin":"","legend":"","description":"","filename":"Table1CMETechniques.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6155030/v1/4603a4ebd936c2110df1d264.pdf"},{"id":82065263,"identity":"c465faa6-360e-4f24-9a3e-ac1df68f2142","added_by":"auto","created_at":"2025-05-06 12:29:25","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":36117,"visible":true,"origin":"","legend":"","description":"","filename":"PostPSMTable2.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6155030/v1/1aeb648c1939af759e0846a2.pdf"},{"id":82065262,"identity":"29c575f4-f2ab-476c-addd-ba56a2fd85df","added_by":"auto","created_at":"2025-05-06 12:29:25","extension":"pdf","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":47326,"visible":true,"origin":"","legend":"","description":"","filename":"SemTtulo.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6155030/v1/6da609f647b02db7d095d9e8.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Minimally- invasive Conventional right colectomy versus complete mesocolic excision for right-colon adenocarcinoma: a single-institution cohort","fulltext":[{"header":"Introduction","content":"\u003cp\u003eColorectal cancer (CRC) is a leading cause of cancer-related morbidity and mortality worldwide. In right colon cancer, the concept of Complete Mesocolic Excision (CME) has gained traction as a potentially superior surgical approach compared to conventional right colectomy. Introduced by Hohenberger \u0026nbsp;in 2009 (01), CME involves meticulous dissection along embryological planes to achieve an intact mesocolon with a higher yield of lymph nodes, which theoretically reduces the risk of local recurrence and improves disease-free survival (DFS) rates. (02)\u003c/p\u003e\n\u003cp\u003eA recent systematic review (03) and meta-analysis, however, \u0026nbsp;has failed to demonstrate significant improvement in three-year overall survival and disease-free survival with CME approach, in addition to no difference in local recurrence and no difference in distant recurrence, in spite of significant increase in 5-year overall survival. Several factors may play a role in this, such as an overall low incidence of local recurrence after curative resection of colon cancer and adjuvant chemotherapy. (04)\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePatient selection may play a crucial role in choosing CME as a technical approach. For \u0026nbsp;more advanced cases or right colon cancer - stages III/IV -, a survival benefit has been more constant in observational trials (05). \u0026nbsp;This may be due to a relative higher incidence - of around 8 % ) of central nodes metastasis in T3 or T4 right colon tumors. (06,07)\u003c/p\u003e\n\u003cp\u003eThe safety of the CME procedure itself is also a matter of debate. Due to the higher distance of the vascular tie and greater mesentery mobilization, it may be associated with greater intraoperative blood loss (08) and postoperative complications. A recent prospective study (09), however, has shown similar complications rates when it is conducted in experienced centers.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn order to analyze this relevant clinical question, we conducted a retrospective analysis of a prospective database of a single center specialized in minimally invasive surgery for colon cancer, comparing the short term safety and long term survival of CME versus conventional right colectomy for the management of right-sided colon cancer.\u0026nbsp;\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cem\u003eStudy design\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eA retrospective analysis of database of patients undergoing elective surgery for right side colon cancer in Albert Einstein Israelite Hospital Sao Paulo, Brazil. All procedures were performed by any of the six experienced oncology surgeons. No learning-curve cases were included for analysis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe research was granted ethical approval by the Institutional Review Board of Hospital Israelita Albert Einstein, which exempted the requirement for informed consent (Protocol Number: CAAE 68495923.6.0000.0071 \u0026nbsp; and in Hospital Albert Einstein IRB ( protocol 6142-24).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn alignment with ethical standards, personal identifiers were anonymized. The study also complied with the Brazilian General Data Protection Law (Lei Geral de Prote\u0026ccedil;\u0026atilde;o de Dados - LGPD) by taking appropriate protective measures. Anonymization techniques were employed to remove any information that could reveal the identities of the subjects.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eInclusion criteria\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eWe included adult (\u0026gt;18 years old) patients diagnosed with right-colon adenocarcinoma. Only minimally invasive right colectomies (laparoscopic or robotic) were considered. The inclusion period was from 2019 to 2024.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eExclusion criteria\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePresence of a second primary tumor.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn addition, for survival analysis, we included only patients with the following findings in the initial pathologic staging for disease-free survival comparison.\u0026nbsp;\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003epathologic T3 or T4 tumor;\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eAny T status with nodal involvement (N1 or higher );\u003c/li\u003e\n \u003cli\u003eSurgical margins free of disease;\u003c/li\u003e\n \u003cli\u003eAbsence of metastatic disease upon diagnosis.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eGroups of study\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSurgical Procedures\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eOnly minimally invasive cases - laparoscopic or robotic- were included.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRobotic technique : Da Vinci robot was utilized for the cases. A single docking with 4 robotic arms, positioned in a straight line from the right iliac region to the xiphoid, plus an auxiliary 12 mm laparoscopic portar were placed. The patient is positioned in a supine position with mild left decubitus and Trendelenburg.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eLaparoscopic technique : Five trocars are placed for the procedure, one 11 mm in the umbilicus for the optics, one 12 mm in the left upper quadrant, and 3 5 mm in the remainder quadrants. The patient is positioned in a supine position, with mild left decubitus and Trendelemburg. At the time of the anastomosis, the patient is returned to a neutral position.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn both approaches, a laparoscopic advanced bipolar scalpel and laparoscopic linear staples were used in the procedure. For the ligation of vessels, only advanced bipolar energy was used, without clips. The anastomosis were lateral, ileal-colonic, isoperistaltic, using 60-mm mid-width linear staplers, concluded with barbed-wire suture. The specimen was retrieved via Maylard auxiliary incision.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;We considered complete mesocolic excision (CME) as right colectomy with central ligation of ileocolic, right colonic and right branch of colon vessels; mesenteric dissection along the embyologic layers; and D3 lymphadenectomy - including Superior Mesenteric Vein (SMV) and lateral Superior mesenteric artery (SMA) lymph nodes. Traditional or conventional right colectomy included ligation of the ileocolic vessels in the SMV root after its exposure, without additional dissection of the D3 nodes.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cu\u003ePostoperative Assessments and Endpoints\u0026nbsp;\u003c/u\u003e\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003ePrimary outcome\u003c/p\u003e\n\u003cp\u003eOur primary outcome was locoregional recurrence, defined as either nodal disease or local recurrence after follow-up for cancer was initiated. Nodal disease was considered positive if imaging findings or pathologic results were indicative of adenocarcinoma recurrence. All patients underwent pos-operative surveillance according to ASCO guidelines, including clinical encounter with clinical oncologist every 3 months, CEA monitoring and anual CT-scan of the chest, abdomen and pelvis. Disease-free survival was defined as the absence of locoregional or distant recurrence after surgery.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cu\u003eSecondary outcomes\u003c/u\u003e\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe secondary outcomes were:\u0026nbsp;\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eOperative time;\u003c/li\u003e\n \u003cli\u003eIn-hospital stay;\u003c/li\u003e\n \u003cli\u003eNumber of harvested lymph nodes;\u003c/li\u003e\n \u003cli\u003ePost-operative surgical complications (including bleeding, unplanned conversion, deep surgical site infection, superficial surgical site infections, anastomotic leak, and death) within 30 days.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cem\u003eStatistical analysis\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eWe conducted survival analysis for disease-free survival counting in months from the operation date - if no adjuvant chemotherapy was conducted - or from the end of adjuvant chemotherapy to build Kaplan-Meier survival curves and to obtain adjusted hazard ratios through Cox regression.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWe also conducted multivariate Poisson regression to obtain risk ratios for loco-regional recurrence across groups after adjusting for:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eAge;\u003c/li\u003e\n \u003cli\u003eSex;\u003c/li\u003e\n \u003cli\u003eBMI;\u003c/li\u003e\n \u003cli\u003ePathologic T stage;\u003c/li\u003e\n \u003cli\u003ePathologic N stage;\u003c/li\u003e\n \u003cli\u003eMismatch repair protein deficiency;\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eAdjuvant chemotherapy ;\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eFirst postoperative CEA level;\u003c/li\u003e\n \u003cli\u003eASA score\u0026nbsp;\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eIn addition, we conducted propensity score matching using STATA nearest neighbor modeling, matching the cohorts by the same variables to analyze our primary outcome more homogeneously. We also conducted univariate and multivariate analyses adjusted for the same confounders for our secondary outcomes utilizing Poisson regression. Due to the relevance of patient selection for CME, we also included a Bayesian variable inclusion regression map, visually highlighting the strongest predictors for nodal recurrence.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll analyses were conducted in STATA 18 for Mac, Standard Edition (serial number: 401806341276. \u0026nbsp;Licensed to: Rodrigo Mois\u0026eacute;s de Almeida Leite; Harvard Medical School).\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cem\u003eDemographics\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eOverall, 154 cases were included for analysis, 26 in the CME cohort, and 128 in the conventional cohort. After applying inclusion and exclusion criteria for the survival analysis, the cohort comprised 26 CME cases and 63 cases in the conventional cohort.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe median age recorded was 65 years old (IQR 60-76) in the conventional cohort and 65.5 years (IQR 55-70) in the CME cohort. Female patients comprised 55.6% of conventional cases and 53.8% of CME cases. There were no significant differences between the groups regarding T or N status and ASA Scores. Patients also had similar baseline characteristics, such as pre-operative hemoglobin and albumin levels. \u0026nbsp;Demographics are summarized in table 1.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eLocoregional recurrence\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNo local recurrences were observed in either group. Nodal recurrence was observed in 6 patients in the conventional cohort (incidence of 9.52%). No nodal recurrence was observed in the CME group. The mean time for nodal recurrence was 28 months (SD 10 months). The strongest predictors for nodal recurrence were pT4 and pN2 stages. Predictors for nodal recurrence are summarized in the Bayesian Regression Model Variable inclusion map (Figure 1).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eComplete mesocolic excision was associated with a significant decrease in nodal recurrence in the various models for analysis conducted.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAfter adjusting for multiple confounders using Poisson Regression, CME was associated with a significant reduction in the risk for nodal recurrence (adjusted RR = 0.08; 95% CI: 0.05 to 0.09; p \u0026lt; 0.001). Also in the propensity-score matching analysis, CME was associated with a significant coefficient of reduction for nodal recurrence (Coef . = -0.14; 95% CI: - 0.23 to -0.05; p = 0.01). Our post PSM validation is presented in table 2. Our Bayesian regression variables inclusion map shows that pathologic T3, T4 and N positive patients were strongly associated with increased nodal recurrence.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eDisease-free survival\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eDisease-free survival was significantly increased in the CME cohort, as demonstrated in the Kaplan-Meier curve ( figure 2). \u0026nbsp;The multivariate survival-time Cox regression showed a significant increase in disease-free survival (HR = 0.03; 95% CI: 0.003 to 0.27; p = 0.002) for the CME treated group. Only one case of death was recorded during the period of \u0026nbsp;follow-up, preventing comparison of overall survival.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePostoperative Outcomes\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eOperative Time\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eCME was associated with a significant increase in total operative time. Median operative time was 135 minutes in the conventional cohort (IQR 109-167), compared to 161 minutes in the CME cohort (IQR 145-200). \u0026nbsp;Surgical outcomes are summarized in table 2.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eIn-hospital stay\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThere was no significant difference between groups regarding in-hospital stay. Median in-hospital stay was 3 days in the CME cohort (IQR 2-5) and 2 days (IQR 2-3) in the conventional group. Surgical outcomes are summarized in table 2.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eHarvested lymph nodes\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eCME was associated with a significant increase in harvested lymph nodes, with 8 extra nodes on average. The median number of nodes was 31 in the conventional cohort (IQR 24-35) and 39 in the CME cohort (IQR 29-45). \u0026nbsp;CME was not \u0026nbsp;associated with positive pathologic nodal disease (40 % vs 31 %, RR 1.28, 95 % CI 0.38 - 4.29), p 0.692). Surgical outcomes are summarized in table 2.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePostoperative complications\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe incidence of major postoperative complications was 23.53 % in the CME group and 18.75% in the conventional group. There was no significant difference in the incidence of major surgical complications both in the univariate (RR = 1.31; 95 % CI: 0.54 to 3.19; p = 0.539) and in the multivariate regression (adjusted RR = 0.93; 95% CI: 0.35 to 2.46; p = 0.896). Only one case of major intraoperative bleeding was reported in the CME cohort, with need of intraoperative blood transfusion. Surgical outcomes are summarized in table 2.\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this retrospective cohort study, minimally-invasive complete mesocolic excision (CME) was associated with reduced nodal recurrence and increase disease-free survival when compared to minimally invasive conventional D2 right colectomy. The benefits were observed even after multiple adjustment and regression methods to reduce the risk for bias and confounding. These findings may translate to a survival benefit of this approach in click practice.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCME in our study was associate with \u0026nbsp;a higher number of harvested lymph nodes. The CME group had a median of 39 lymph nodes compared to 31 in the conventional group, yielding an average of eight additional nodes. This increased lymph node retrieval has been demonstrated in multiple studies comparing CME to conventional techniques, of around 8 additional harvested nodes ( 09 ), and may be associated with more accurate staging, increase in adjuvant chemotherapy and reduced recurrence (11).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOur study showed a significant association of CME with reduced nodal recurrence. Nodal recurrence was observed in 9.52% of patients in the conventional cohort as opposed to zero events in the CME cohort. The mean time to nodal recurrence was 28 months. The strongest predictors for local recurrence were pT4 and pN2 stages, as consistent with the literature. CME showed a consistent reduction in nodal recurrence risk across various models, including adjusted and propensity-score matching analyses.\u003c/p\u003e\n\u003cp\u003eOur analysis was also associated with a significant improvement in disease-free survival (DFS) for patients undergoing CME, as demonstrated in the Kaplan-Meier and Cox-regression model. Patient selection may play a crucial role in this outcome. We only included for our survival analysis patients with pT3, pT4 or pN + disease. The recent RELARC trial (12) failed to show a significant improvement in 3 years DFS with CME, but the profile of patients was different, with inclusion of pT2N0 patients. Also, the location of tumors within the right colon (cecum vs hepatic flexure tumors) \u0026nbsp; (13) is also associated with differences in central nodes metastasis and may affect findings. Our findings correlate, however, with a recent systematic review (9) showing a survival improved DFS with the same profile of patients included in our analysis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCME was associated with a longer operative time compared to conventional colectomy, with median times of 161 minutes for CME and 135 minutes for conventional surgery. This increase is expected given the complexity of the CME procedure, which involves more extensive dissection and mesentery mobilization. Despite the longer operative time, the median in-hospital stay did not differ significantly between the two groups, indicating that the longer surgery duration does not necessarily lead to extended hospitalization or increased postoperative morbidity.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe incidence of major postoperative complications was not significantly different between the CME and conventional groups. Major complications occurred in 23.1% of CME patients and 17.5% of conventional colectomy patients, with no statistically significant difference in both univariate (RR = 1.31; 95% CI: 0.54 to 3.19; p = 0.539) and multivariate analyses (adjusted RR = 0.93; 95% CI: -0.35 to 2.46; p = 0.896). Notably, we did not record any event of superior mesenteric artery lesion of major vascular event. This shows the good safety profile of the CME procedure when conducted in specialized, high volume centers.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOur study has several limitations. Due to the observational nature, the risk of residual bias cannot be excluded. Also, factors as the decision to conduct CME in the first place may be associated with selection bias and inter-surgeon variation. In addition, nodal recurrence had an overall low incidence (only 6 cases), with may impact in model overfitting for our multivariate analysis. We also observed a trend towards greater robotic approach in the CME cohort, which may impact results. However, we conducted multiple adjustments to reduce the influence of bias and systematic error, and all procedures were conducted by the same team of specialized surgeons in a high volume academic center for the treatment of colon cancer.\u0026nbsp;\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eOur study demonstrates that CME is a safe and feasible surgical technique for the management of right-side colon adenocarcinoma, associated with increased lymph node yield and comparable post-operative recovery. Also, our results point to improved oncological outcomes and increased disease survival when it was performed for a select group of high risk patients - \u0026nbsp;T3, T4, N positive without distant metastasis upon diagnosis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cem\u003eConflicts of interest :\u003c/em\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eDrs. Leite, Ramos, Portilho, Tustumi, Stolzemburg, \u0026nbsp;Gerbasi, Horcel, Pandini, Ricciardi, Seid and Araujo have no conflicts of interest related to the topic to disclose.\u0026nbsp;\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cem\u003eFunding :\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThis study was self funded.\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eHohenberger W, Weber K, Matzel K, Papadopoulos T, Merkel S. Standardized surgery for colonic cancer: complete mesocolic excision and central ligation--technical notes and outcome. \u003cem\u003eColorectal Dis\u003c/em\u003e. 2009;11(4):354-365. doi:10.1111/j.1463-1318.2008.01735.x\u003c/li\u003e\n\u003cli\u003eWest NP, Hohenberger W, Weber K, Perrakis A, Finan PJ, Quirke P. Complete mesocolic excision with central vascular ligation produces an oncologically superior specimen compared with standard surgery for carcinoma of the colon. \u003cem\u003eJ Clin Oncol\u003c/em\u003e. 2010;28(2):272-278. doi:10.1200/JCO.2009.24.1448\u003c/li\u003e\n\u003cli\u003eDe Lange G, Davies J, Toso C, Meurette G, Ris F, Meyer J. Complete mesocolic excision for right hemicolectomy: an updated systematic review and meta-analysis. \u003cem\u003eTech Coloproctol\u003c/em\u003e. 2023;27(11):979-993. doi:10.1007/s10151-023-02853-8\u003c/li\u003e\n\u003cli\u003eMalakorn S, Ouchi A, Hu CY, et al. Tumor Sidedness, Recurrence, and Survival After Curative Resection of Localized Colon Cancer. \u003cem\u003eClin Colorectal Cancer\u003c/em\u003e. 2021;20(1):e53-e60. doi:10.1016/j.clcc.2020.08.007\u003c/li\u003e\n\u003cli\u003eMazzarella G, Muttillo EM, Picardi B, Rossi S, Muttillo IA. Complete mesocolic excision and D3 lymphadenectomy with central vascular ligation in right-sided colon cancer: a systematic review of postoperative outcomes, tumor recurrence and overall survival. \u003cem\u003eSurg Endosc\u003c/em\u003e. 2021;35(9):4945-4955. doi:10.1007/s00464-021-08529-4\u003c/li\u003e\n\u003cli\u003ePaquette IM, Madoff RD, Sigurdson ER, Chang GJ (2018) Impactof proximal vascular ligation on survival of patients with coloncancer. Ann Surg Oncol 25:38\u0026ndash;4547.\u0026nbsp;\u003c/li\u003e\n\u003cli\u003eSammour T, Malakorn S, Thampy R, Kaur H, Bednarski BK,Messick CA, Taggart M, Chang GJ, You YN (2019) Selectivecentral vascular ligation (D3 lymphadenectomy) in patients under-going minimally invasive complete mesocolic excision for coloncancer: optimizing the risk\u0026ndash;benefit equation. Color Dis 22:53\u0026ndash;61\u003c/li\u003e\n\u003cli\u003eWang C, Gao Z, Shen K, et al. Safety, quality and effect of complete mesocolic excision vs non-complete mesocolic excision in patients with colon cancer: a systemic review and meta-analysis. \u003cem\u003eColorectal Dis\u003c/em\u003e. 2017;19(11):962-972. doi:10.1111/codi.13900\u003c/li\u003e\n\u003cli\u003eFerri V, Vicente E, Quijano Y, Duran H, Diaz E, Fabra I, Malave L, Agresott R, Isernia R, Cardinal-Fernandez P, Ruiz P, Nola V, de Nobili G, Ielpo B, Caruso R. Right-side colectomy with complete mesocolic excision vs conventional right-side colectomy in the treatment of colon cancer: a systematic review and meta-analysis. Int J Colorectal Dis. 2021 Sep;36(9):1885-1904. doi: 10.1007/s00384-021-03951-5. Epub 2021 May 13. PMID: 33983451.\u003c/li\u003e\n\u003cli\u003eWillard CD, Kjaestad E, Stimec BV, Edwin B, Ignjatovic D; RCC Study Group. Preoperative anatomical road mapping reduces variability of operating time, estimated blood loss, and lymph node yield in right colectomy with extended D3 mesenterectomy for cancer. \u003cem\u003eInt J Colorectal Dis\u003c/em\u003e. 2019;34(1):151-160. doi:10.1007/s00384-018-3177-5\u003c/li\u003e\n\u003cli\u003eBamboat ZM, Deperalta D, Dursun A, Berger DL, Bordeianou L. Factors affecting lymph node yield from patients undergoing colectomy for cancer. \u003cem\u003eInt J Colorectal Dis\u003c/em\u003e. 2011;26(9):1163-1168. doi:10.1007/s00384-011-1240-6\u003c/li\u003e\n\u003cli\u003eLu J, Xing J, Zang L, Zhang C, Xu L, Zhang G, He Z, Sun Y, Feng Y, Du X, Hu S, Chi P, Huang Y, Wang Z, Zhong M, Wu A, Zhu A, Li F, Xu J, Kang L, Suo J, Deng H, Ye Y, Ding K, Xu T, Zhang Y, Zhang Z, Zheng M, Su X, Xiao Y; RELARC study group. Extent of Lymphadenectomy for Surgical Management of Right-Sided Colon Cancer: The Randomized Phase III RELARC Trial. J Clin Oncol. 2024 Nov 20;42(33):3957-3966. doi: 10.1200/JCO.24.00393. Epub 2024 Aug 27. PMID: 39190853.\u003c/li\u003e\n\u003cli\u003eBertelsen CA, Kirkegaard-Klitbo A, Nielsen M, Leotta SM, Daisuke F, G\u0026ouml;genur I. Pattern of Colon Cancer Lymph Node Metastases in Patients Undergoing Central Mesocolic Lymph Node Excision: A Systematic Review. 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PMID: 27824707.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\n\u003cp\u003eTables 1 and 2 are available in the Supplementary Files section.\u003c/p\u003e\n"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"colon cancer, complete mesocolic excision, colorectal cancer, D3 lymphadectomy, right colon-cancer, central vessel ligation, robotic surgery, laparoscopic surgery, minimally invasive colectomy ","lastPublishedDoi":"10.21203/rs.3.rs-6155030/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6155030/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIntroduction : The benefits of complete mesocolic excision (CME) versus conventional right colectomy (CRH) in right-side colon cancer remain to be defined, as it relates to reduced nodal recurrence and increase in disease-free survival (DFS). Optimal patient selection also seems to play a crucial role in choosing the best surgical technique for right-colon cancer.\u003c/p\u003e\n\u003cp\u003eMethods : a retrospective analysis of a prospective, single center database analyzing minimally-invasive CME vs CRH in right side colon cancer. Only patients with free surgical margins and without distant metastasis were included for analysis. Outcomes analyzed included local recurrence, nodal recurrence, DFS, length of stay, node harvesting and major postoperative complications. The analysis was adjusted for multiple confounders, including Age; Sex; BMI; Pathologic T stage; Pathologic N stage; Mismatch repair protein deficiency; \u0026nbsp;Adjuvant chemotherapy ; First postoperative CEA level; ASA score.\u003c/p\u003e\n\u003cp\u003eResults : CME presented a similar safety profile, with increased in lymph node yield. CME was associated with a significant reduction in the risk for nodal recurrence (adjusted RR = 0.08; 95% CI: 0.05 to 0.09; p \u0026lt; 0.001). Also in the propensity-score matching analysis, CME was associated with a significant coefficient of reduction for nodal recurrence (Coef . = -0.14; 95% CI: - 0.23 to -0.05; p = 0.01). An improvement in disease-free survival was also observed (HR = 0.03; 95% CI: 0.003 to 0.27; p = 0.002) in patients with pT3/pT4 or pN+ disease.\u003c/p\u003e\n\u003cp\u003eMeaning : Minimally-invasive CME may be associated with decrease in nodal recurrence and increase disease-free survival in patients with right colon cancer.\u003c/p\u003e","manuscriptTitle":"Minimally- invasive Conventional right colectomy versus complete mesocolic excision for right-colon adenocarcinoma: a single-institution cohort","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-06 12:29:20","doi":"10.21203/rs.3.rs-6155030/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"383c8518-486b-4b15-aa48-a04ac1fa73e2","owner":[],"postedDate":"May 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-09-24T19:09:45+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-06 12:29:20","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6155030","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6155030","identity":"rs-6155030","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}